Merge remote-tracking branch 'upstream/master' into search-rebased

# Conflicts:
#	Emby.Server.Implementations/Library/LibraryManager.cs
#	Jellyfin.Server.Implementations/Item/PeopleRepository.cs
#	MediaBrowser.Controller/Library/ILibraryManager.cs
#	MediaBrowser.Controller/Persistence/IPeopleRepository.cs

12 files changed, 193 insertions, 38 deletions

diff --git a/MediaBrowser.Controller/Collections/ICollectionManager.cs b/MediaBrowser.Controller/Collections/ICollectionManager.cs
index 206b5ac426..8d5d54ffd9 100644
--- a/MediaBrowser.Controller/Collections/ICollectionManager.cs
+++ b/MediaBrowser.Controller/Collections/ICollectionManager.cs
@@ -58,6 +58,14 @@ namespace MediaBrowser.Controller.Collections
         IEnumerable<BaseItem> CollapseItemsWithinBoxSets(IEnumerable<BaseItem> items, User user);
 
         /// <summary>
+        /// Gets the collections accessible to the supplied user that contain the provided item.
+        /// </summary>
+        /// <param name="user">The user.</param>
+        /// <param name="itemId">The item identifier.</param>
+        /// <returns>The collections containing the item.</returns>
+        IEnumerable<BoxSet> GetCollectionsContainingItem(User user, Guid itemId);
+
+        /// <summary>
         /// Gets the folder where collections are stored.
         /// </summary>
         /// <param name="createIfNeeded">Will create the collection folder on the storage if set to true.</param>
diff --git a/MediaBrowser.Controller/Entities/BaseItem.cs b/MediaBrowser.Controller/Entities/BaseItem.cs
index 4cdcaabbb1..e24b60f69f 100644
--- a/MediaBrowser.Controller/Entities/BaseItem.cs
+++ b/MediaBrowser.Controller/Entities/BaseItem.cs
@@ -94,6 +94,8 @@ namespace MediaBrowser.Controller.Entities
 
         private string _name;
 
+        private string _originalLanguage;
+
         public const char SlugChar = '-';
 
         protected BaseItem()
@@ -217,7 +219,11 @@ namespace MediaBrowser.Controller.Entities
         public string OriginalTitle { get; set; }
 
         [JsonIgnore]
-        public string OriginalLanguage { get; set; }
+        public string OriginalLanguage
+        {
+            get => _originalLanguage;
+            set => _originalLanguage = LocalizationManager?.FindLanguageInfo(value)?.TwoLetterISOLanguageName ?? value;
+        }
 
         /// <summary>
         /// Gets or sets the id.
@@ -1564,7 +1570,7 @@ namespace MediaBrowser.Controller.Entities
         }
 
         /// <summary>
-        /// Gets the preferred metadata language.
+        /// Gets the preferred metadata country code.
         /// </summary>
         /// <returns>System.String.</returns>
         public string GetPreferredMetadataCountryCode()
@@ -1598,6 +1604,15 @@ namespace MediaBrowser.Controller.Entities
             return lang;
         }
 
+        /// <summary>
+        /// Gets the original language of the item, inheriting from parent items if necessary.
+        /// </summary>
+        /// <returns>System.String.</returns>
+        public virtual string GetInheritedOriginalLanguage()
+        {
+            return OriginalLanguage;
+        }
+
         public virtual bool IsSaveLocalMetadataEnabled()
         {
             if (SourceType == SourceType.Channel)
diff --git a/MediaBrowser.Controller/Entities/TV/Episode.cs b/MediaBrowser.Controller/Entities/TV/Episode.cs
index dbe6f94dfd..42e4f79942 100644
--- a/MediaBrowser.Controller/Entities/TV/Episode.cs
+++ b/MediaBrowser.Controller/Entities/TV/Episode.cs
@@ -153,6 +153,12 @@ namespace MediaBrowser.Controller.Entities.TV
             return 16.0 / 9;
         }
 
+        /// <inheritdoc />
+        public override string GetInheritedOriginalLanguage()
+        {
+            return OriginalLanguage ?? Series?.GetInheritedOriginalLanguage();
+        }
+
         public override List<string> GetUserDataKeys()
         {
             var list = base.GetUserDataKeys();
diff --git a/MediaBrowser.Controller/Entities/TV/Season.cs b/MediaBrowser.Controller/Entities/TV/Season.cs
index f70f7dfb4c..e96ed05a5e 100644
--- a/MediaBrowser.Controller/Entities/TV/Season.cs
+++ b/MediaBrowser.Controller/Entities/TV/Season.cs
@@ -128,6 +128,12 @@ namespace MediaBrowser.Controller.Entities.TV
             return result;
         }
 
+        /// <inheritdoc />
+        public override string GetInheritedOriginalLanguage()
+        {
+            return OriginalLanguage ?? Series?.GetInheritedOriginalLanguage();
+        }
+
         public override string CreatePresentationUniqueKey()
         {
             if (IndexNumber.HasValue)
diff --git a/MediaBrowser.Controller/Entities/Video.cs b/MediaBrowser.Controller/Entities/Video.cs
index 80bcd62dcd..44cae5197a 100644
--- a/MediaBrowser.Controller/Entities/Video.cs
+++ b/MediaBrowser.Controller/Entities/Video.cs
@@ -278,6 +278,17 @@ namespace MediaBrowser.Controller.Entities
             return linkedVersionCount + localVersionCount + 1;
         }
 
+        /// <inheritdoc />
+        public override string GetInheritedOriginalLanguage()
+        {
+            if (ExtraType.GetValueOrDefault() == Model.Entities.ExtraType.Trailer)
+            {
+                return GetOwner()?.GetInheritedOriginalLanguage();
+            }
+
+            return OriginalLanguage ?? GetOwner()?.GetInheritedOriginalLanguage();
+        }
+
         public override List<string> GetUserDataKeys()
         {
             var list = base.GetUserDataKeys();
diff --git a/MediaBrowser.Controller/Library/IBatchLocalSimilarItemsProvider.cs b/MediaBrowser.Controller/Library/IBatchLocalSimilarItemsProvider.cs
new file mode 100644
index 0000000000..af49711606
--- /dev/null
+++ b/MediaBrowser.Controller/Library/IBatchLocalSimilarItemsProvider.cs
@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using MediaBrowser.Controller.Entities;
+
+namespace MediaBrowser.Controller.Library;
+
+/// <summary>
+/// A local similar items provider that supports batch queries across multiple source items.
+/// Implementations share access filtering and entity loading across all sources for better performance.
+/// </summary>
+public interface IBatchLocalSimilarItemsProvider : ISimilarItemsProvider
+{
+    /// <summary>
+    /// Gets similar items for multiple source items in a single batch.
+    /// </summary>
+    /// <param name="sourceItems">The source items to find similar items for.</param>
+    /// <param name="query">The query options.</param>
+    /// <param name="cancellationToken">The cancellation token.</param>
+    /// <returns>Per-source-item results keyed by source item ID.</returns>
+    Task<Dictionary<Guid, IReadOnlyList<BaseItem>>> GetBatchSimilarItemsAsync(
+        IReadOnlyList<BaseItem> sourceItems,
+        SimilarItemsQuery query,
+        CancellationToken cancellationToken);
+}
diff --git a/MediaBrowser.Controller/Library/ILibraryManager.cs b/MediaBrowser.Controller/Library/ILibraryManager.cs
index d794205f00..c23eba75ef 100644
--- a/MediaBrowser.Controller/Library/ILibraryManager.cs
+++ b/MediaBrowser.Controller/Library/ILibraryManager.cs
@@ -598,12 +598,13 @@ namespace MediaBrowser.Controller.Library
         IReadOnlyList<string> GetPeopleNames(InternalPeopleQuery query);
 
         /// <summary>
-        /// Gets the people names per item for a batch of item IDs in a single DB round-trip.
+        /// Gets distinct people names for multiple items.
         /// </summary>
-        /// <param name="itemIds">The item IDs to look up.</param>
-        /// <param name="personTypes">Optional person types to include. Empty for all.</param>
-        /// <returns>Dictionary keyed by item id; values are the per-item people names. Items with no people are absent.</returns>
-        IReadOnlyDictionary<Guid, IReadOnlyList<string>> GetPeopleNamesByItem(IReadOnlyList<Guid> itemIds, IReadOnlyList<string> personTypes);
+        /// <param name="itemIds">The item IDs.</param>
+        /// <param name="personTypes">The person types to include.</param>
+        /// <param name="limit">Maximum number of names.</param>
+        /// <returns>The distinct people names.</returns>
+        IReadOnlyList<string> GetPeopleNamesByItems(IReadOnlyList<Guid> itemIds, IReadOnlyList<string> personTypes, int limit);
 
         /// <summary>
         /// Queries the items.
diff --git a/MediaBrowser.Controller/Library/ISimilarItemsManager.cs b/MediaBrowser.Controller/Library/ISimilarItemsManager.cs
index 0ced6f71ee..36fa547eeb 100644
--- a/MediaBrowser.Controller/Library/ISimilarItemsManager.cs
+++ b/MediaBrowser.Controller/Library/ISimilarItemsManager.cs
@@ -6,6 +6,7 @@ using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Dto;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Model.Configuration;
+using MediaBrowser.Model.Dto;
 
 namespace MediaBrowser.Controller.Library;
 
@@ -47,4 +48,23 @@ public interface ISimilarItemsManager
         int? limit,
         LibraryOptions? libraryOptions,
         CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Builds movie recommendations for a user: a mix of similar-items and person-based categories,
+    /// scheduled round-robin and capped to <paramref name="categoryLimit"/>.
+    /// </summary>
+    /// <param name="user">The user the recommendations are for. May be <see langword="null"/> for anonymous access.</param>
+    /// <param name="parentId">The library/folder to localize the search to. Pass <see cref="Guid.Empty"/> to use the root.</param>
+    /// <param name="categoryLimit">Maximum number of recommendation categories to return.</param>
+    /// <param name="itemLimit">Maximum number of items per category.</param>
+    /// <param name="dtoOptions">DTO options used when querying the library.</param>
+    /// <param name="cancellationToken">The cancellation token.</param>
+    /// <returns>The list of recommendation categories, ordered by <see cref="RecommendationType"/>.</returns>
+    Task<IReadOnlyList<SimilarItemsRecommendation>> GetMovieRecommendationsAsync(
+        User? user,
+        Guid parentId,
+        int categoryLimit,
+        int itemLimit,
+        DtoOptions dtoOptions,
+        CancellationToken cancellationToken);
 }
diff --git a/MediaBrowser.Controller/Library/SimilarItemsRecommendation.cs b/MediaBrowser.Controller/Library/SimilarItemsRecommendation.cs
new file mode 100644
index 0000000000..71346fcadf
--- /dev/null
+++ b/MediaBrowser.Controller/Library/SimilarItemsRecommendation.cs
@@ -0,0 +1,32 @@
+using System;
+using System.Collections.Generic;
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Model.Dto;
+
+namespace MediaBrowser.Controller.Library;
+
+/// <summary>
+/// A recommendation category derived from a baseline item, holding similar items prior to DTO conversion.
+/// </summary>
+public sealed class SimilarItemsRecommendation
+{
+    /// <summary>
+    /// Gets the display name of the baseline item the recommendation is based on.
+    /// </summary>
+    public required string BaselineItemName { get; init; }
+
+    /// <summary>
+    /// Gets an identifier for the recommendation category.
+    /// </summary>
+    public required Guid CategoryId { get; init; }
+
+    /// <summary>
+    /// Gets the recommendation type.
+    /// </summary>
+    public required RecommendationType RecommendationType { get; init; }
+
+    /// <summary>
+    /// Gets the similar items for the baseline, ordered by relevance.
+    /// </summary>
+    public required IReadOnlyList<BaseItem> Items { get; init; }
+}
diff --git a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
index 8f6e36bce4..ff8d84d45e 100644
--- a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
+++ b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
@@ -86,6 +86,7 @@ namespace MediaBrowser.Controller.MediaEncoding
         private readonly Version _minFFmpegQsvVppScaleModeOption = new Version(6, 0);
         private readonly Version _minFFmpegRkmppHevcDecDoviRpu = new Version(7, 1, 1);
         private readonly Version _minFFmpegReadrateCatchupOption = new Version(8, 0);
+        private readonly Version _minFFmpegNoiseBsfDrop = new Version(5, 0);
 
         private static readonly string[] _videoProfilesH264 =
         [
@@ -1547,20 +1548,61 @@ namespace MediaBrowser.Controller.MediaEncoding
 
         public string GetAudioBitStreamArguments(EncodingJobInfo state, string segmentContainer, string mediaSourceContainer)
         {
-            var bitStreamArgs = string.Empty;
+            var filters = new List<string>();
+
+            var noiseFilter = GetCopiedAudioTrimBsf(state);
+            if (!string.IsNullOrEmpty(noiseFilter))
+            {
+                filters.Add(noiseFilter);
+            }
+
             var segmentFormat = GetSegmentFileExtension(segmentContainer).TrimStart('.');
 
             // Apply aac_adtstoasc bitstream filter when media source is in mpegts.
             if (string.Equals(segmentFormat, "mp4", StringComparison.OrdinalIgnoreCase)
                 && (string.Equals(mediaSourceContainer, "ts", StringComparison.OrdinalIgnoreCase)
                     || string.Equals(mediaSourceContainer, "aac", StringComparison.OrdinalIgnoreCase)
-                    || string.Equals(mediaSourceContainer, "hls", StringComparison.OrdinalIgnoreCase)))
+                    || string.Equals(mediaSourceContainer, "hls", StringComparison.OrdinalIgnoreCase))
+                && IsAAC(state.AudioStream))
             {
-                bitStreamArgs = GetBitStreamArgs(state, MediaStreamType.Audio);
-                bitStreamArgs = string.IsNullOrEmpty(bitStreamArgs) ? string.Empty : " " + bitStreamArgs;
+                filters.Add("aac_adtstoasc");
             }
 
-            return bitStreamArgs;
+            return filters.Count == 0
+                ? string.Empty
+                : " -bsf:a " + string.Join(',', filters);
+        }
+
+        // When video is transcoded, accurate_seek (the default) trims video to the
+        // exact seek point via decoder-side frame discard. But stream-copied audio
+        // bypasses the decoder, so it starts from the nearest keyframe — potentially
+        // seconds before the target. Use the noise bsf to drop copied audio packets
+        // before the seek target, achieving the same trim precision without
+        // re-encoding. The noise bsf's drop= parameter requires ffmpeg >= 5.0.
+        // Important: make sure not to use it with wtv because it breaks seeking
+        private string GetCopiedAudioTrimBsf(EncodingJobInfo state)
+        {
+            if (state.TranscodingType is not TranscodingJobType.Hls
+                || !state.IsVideoRequest
+                || IsCopyCodec(state.OutputVideoCodec)
+                || !IsCopyCodec(state.OutputAudioCodec)
+                || string.Equals(state.InputContainer, "wtv", StringComparison.OrdinalIgnoreCase)
+                || _mediaEncoder.EncoderVersion < _minFFmpegNoiseBsfDrop)
+            {
+                return null;
+            }
+
+            var startTicks = state.BaseRequest.StartTimeTicks ?? 0;
+            if (startTicks <= 0)
+            {
+                return null;
+            }
+
+            var seekSeconds = startTicks / (double)TimeSpan.TicksPerSecond;
+            return string.Format(
+                CultureInfo.InvariantCulture,
+                "noise=drop='lt(pts*tb\\,{0:F3})'",
+                seekSeconds);
         }
 
         public static string GetSegmentFileExtension(string segmentContainer)
@@ -2014,11 +2056,15 @@ namespace MediaBrowser.Controller.MediaEncoding
                 args += keyFrameArg + gopArg;
             }
 
-            // global_header produced by AMD HEVC VA-API encoder causes non-playable fMP4 on iOS
+            // The in-band Parameter Sets generated by the AMD HEVC VA-API encoder is inconsistent
+            // with the extradata generated by ffmpeg, causing decoding failures when using hvc1.
             if (string.Equals(codec, "hevc_vaapi", StringComparison.OrdinalIgnoreCase)
                 && _mediaEncoder.IsVaapiDeviceAmd)
             {
-                args += " -flags:v -global_header";
+                // Extracting the extradata from the in-band PS to bypass the issue.
+                // This can be removed once the issue is resolved in libva or Mesa.
+                // Transcoding is unavoidable here, so using BSF will not conflict with BSF in remuxing.
+                args += " -flags:v -global_header -bsf:v extract_extradata=remove=0";
             }
 
             return args;
@@ -3002,23 +3048,6 @@ namespace MediaBrowser.Controller.MediaEncoding
                 }
 
                 seekParam += string.Format(CultureInfo.InvariantCulture, "-ss {0}", _mediaEncoder.GetTimeParameter(seekTick));
-
-                if (state.IsVideoRequest)
-                {
-                    // If we are remuxing, then the copied stream cannot be seeked accurately (it will seek to the nearest
-                    // keyframe). If we are using fMP4, then force all other streams to use the same inaccurate seeking to
-                    // avoid A/V sync issues which cause playback issues on some devices.
-                    // When remuxing video, the segment start times correspond to key frames in the source stream, so this
-                    // option shouldn't change the seeked point that much.
-                    // Important: make sure not to use it with wtv because it breaks seeking
-                    if (state.TranscodingType is TranscodingJobType.Hls
-                        && string.Equals(segmentContainer, "mp4", StringComparison.OrdinalIgnoreCase)
-                        && (IsCopyCodec(state.OutputVideoCodec) || IsCopyCodec(state.OutputAudioCodec))
-                        && !string.Equals(state.InputContainer, "wtv", StringComparison.OrdinalIgnoreCase))
-                    {
-                        seekParam += " -noaccurate_seek";
-                    }
-                }
             }
 
             return seekParam;
diff --git a/MediaBrowser.Controller/Persistence/ILinkedChildrenService.cs b/MediaBrowser.Controller/Persistence/ILinkedChildrenService.cs
index d0cddf54a6..a4614fc125 100644
--- a/MediaBrowser.Controller/Persistence/ILinkedChildrenService.cs
+++ b/MediaBrowser.Controller/Persistence/ILinkedChildrenService.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using Jellyfin.Data.Enums;
 using MediaBrowser.Controller.Entities.Audio;
 using LinkedChildType = MediaBrowser.Controller.Entities.LinkedChildType;
 
@@ -29,8 +30,9 @@ public interface ILinkedChildrenService
     /// Gets parent IDs that reference the specified child with LinkedChildType.Manual.
     /// </summary>
     /// <param name="childId">The child item ID.</param>
+    /// <param name="parentType">Optional parent item type filter.</param>
     /// <returns>List of parent IDs that reference the child.</returns>
-    IReadOnlyList<Guid> GetManualLinkedParentIds(Guid childId);
+    IReadOnlyList<Guid> GetManualLinkedParentIds(Guid childId, BaseItemKind? parentType = null);
 
     /// <summary>
     /// Updates LinkedChildren references from one child to another.
diff --git a/MediaBrowser.Controller/Persistence/IPeopleRepository.cs b/MediaBrowser.Controller/Persistence/IPeopleRepository.cs
index 3a3b2bfb1f..7474130ec4 100644
--- a/MediaBrowser.Controller/Persistence/IPeopleRepository.cs
+++ b/MediaBrowser.Controller/Persistence/IPeopleRepository.cs
@@ -34,12 +34,11 @@ public interface IPeopleRepository
     IReadOnlyList<string> GetPeopleNames(InternalPeopleQuery filter);
 
     /// <summary>
-    /// Gets the people names per item for a batch of item IDs, preserving per-item list order.
-    /// One database round-trip for the whole batch; grouped by item id in memory.
-    /// Items with no people are omitted from the returned dictionary.
+    /// Gets distinct people names for multiple items efficiently by querying from the mapping table.
     /// </summary>
     /// <param name="itemIds">The item IDs to get people for.</param>
-    /// <param name="personTypes">Optional person types to include (e.g. "Actor", "Director"). Empty for all.</param>
-    /// <returns>Dictionary keyed by item id; values are the per-item people names.</returns>
-    IReadOnlyDictionary<Guid, IReadOnlyList<string>> GetPeopleNamesByItem(IReadOnlyList<Guid> itemIds, IReadOnlyList<string> personTypes);
+    /// <param name="personTypes">The person types to include (e.g. "Actor", "Director").</param>
+    /// <param name="limit">Maximum number of names to return.</param>
+    /// <returns>The distinct people names.</returns>
+    IReadOnlyList<string> GetPeopleNamesByItems(IReadOnlyList<Guid> itemIds, IReadOnlyList<string> personTypes, int limit);
 }